[Top] [All Lists]

Re: [openpgp] Intent to deprecate: Insecure primitives

2015-03-13 20:30:48
Yes, I can get behind that.  Make it so!  Users should be presented with
secure defaults and not given the opportunity to unknowingly decrease
security.  Deprecating lower-security but equivalently performant
algorithms is especially commendable.

That said, archived encrypted data may require decryption support well
into the future.  OpenPGP-encrypted data is not ephemeral like
TLS-encrypted data.

--Falcon Darkstar Momot

On 13/03/2015 18:22, David Leon Gil wrote:
First, the fait accompli:

1. Yahoo and Google have both already deprecated and removed support
for the following packet type specified for use with OpenPGPv4:

    Tag 9 (symmetrically encrypted) packets

These packets provide unauthenticated encryption and -- if supported
-- can be used in a downgrade attack on senders who only use SEIPD
packets. See
for details.

2. Yahoo and GnuPG have both already deprecated V3 public keys for any
use. We recommend that other implementations do the same.


Second, the near future:

Yahoo has deprecated, and intends to disable support for all uses, of
the following primitives and packet types specified for use with
OpenPGP v4:

- Symmetric cipher algorithms: IDEA, TDES, CAST5, Blowfish, Twofish
- Asymmetric algorithms, generally: RSA-ES, DSA.
- Asymmetric algorithms, unless > 3070 bit key length: RSA-S, RSA-E, ELG-E.
- Compression algorithms: ZLIB. (It provides no benefits over DEFLATE,
and is more malleable.)
- Hash algorithms: MD5, SHA-1, RIPEMD160, SHA-2-224.

We do not, at present, support any of the CAMELLIA algorithms or
BZIP2. It is unlikely that we will do so in future.

At present, we anticipate removing support for these primitives no
later than May 1, 2015.

Attachment: smime.p7s
Description: S/MIME Cryptographic Signature

openpgp mailing list